Dreadbark was a tough woody material that grew on dreadwood worms naturally.
The dreadwood worm’s body was covered in a thick armour not unlike the carapace one might find on an insect or arachnid. Instead of chitin, this shell was made of bark similar to dunbark. Dreadwood bark, often called “dreadbark”, could be up to 5 centimeters thick along a dreadwood worm’s head.
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The Tukumen often used dreadbark as an ingredient in their armour.